Interposers for inter-chip interconnects should perform stably under high-temperature conditions and rapid temperature change due to the heat generated by mounted large-scale integration (LSI) chips. Athermal silicon optical interposers integrated with quantum dot lasers and other temperature-insensitive components on a single silicon substrate are demonstrated, and error-free data links at 12.5 Gbit/s operating from 25 to 125°C are achieved without any bias adjustment. Since maximum junction temperatures in most LSIs have been below 125°C now and will be in the future, the interposers are tolerant of heat generated by LSIs, and are suitable for inter-chip interconnects.Introduction: We previously proposed a photonics-electronics convergence system to solve bandwidth bottlenecks in inter-chip interconnects and demonstrated silicon optical interposers fully integrated with optical components on a silicon substrate, achieving a high bandwidth density of 30 Tbit/s/cm 2 at room temperature [1]. In practical use, the optical interposers should perform stably under high-temperature conditions and rapid temperature change due to the heat generated by mounted large-scale integration (LSI) chips. As the output power of conventional laser diodes (LDs) usually declines as temperature rises, the system particularly requires temperature-insensitive LDs. In the work reported in this Letter, we fabricated athermal silicon optical interposers integrated with quantum dot (QD) LDs [2, 3], which have temperature-insensitive characteristics, and demonstrate their link performance over a wide temperature range.